Imidazoline promoter overbased calcium sulfonates

Abstract

A composition and process for preparing an overbased calcium sulfonate, in which a specific class of compounds is employed as promoters in making overbased calcium sulfonates. These promoters give an enhanced efficiency of the conversion of lime to an oil-soluble dispersion of calcium carbonate. Low post-carbonation solids and high TBN (total base number of alkaline reserve) result from this improve promoter system. The process for preparing highly basic calcium sulfonate includes contacting an acidic gas at a temperature between 60° F. to 103° F., with a mixture of a sulfonic acid or calcium salt thereof, a hydrocarbon solvent, calcium hydroxide, a small quantity of co-promoter methanol, and up to 1.0% by weight of a compound with formula: ##STR1## where X=O, S, ═CH, --CH 2 , --NH or --N═ Y=O, N or S; R=H or, C 1 to C 50 ; and R'=H, CH 2 CH 2 OH, or CH 2 CH 2 NH 2 when Y is N, and zero when Y is O or S. The above membered cyclic rings can be saturated and unsaturated, and include as preferred compounds, imidazolines, oxazolines and pyrroles, and saturated and unsaturated analogs thereof.

What is claimed is: 
     
       1. A promoter for and with an overbased calcium sulfonate comprising; a cyclic compound present in an amount of up to 1.0% of the overbased calcium sulfonate, and having the formula: ##STR11## where Y=0, N or S; R=H or, C 1  TO C 50  ; and   R'=H, CH 2  CH 2  OH, or CH 2  CH 2  NH 2  when Y is N, and zero when Y is O or S.   
     
     
       2. The promoter of claim 1, wherein R is a C 18  -C 24  alkyl group. 
     
     
       3. The promoter of claim 1, further comprising a C 1  -C 6  alkanol co-promoter. 
     
     
       4. The promoter of claim 1, wherein the total weight of promoter and co-promoter is less than about 8% of the overbased calcium sulfonate, and the overbased calcium sulfonate has a TBN of at least about 300. 
     
     
       5. The promoter of claim 1, said cyclic compound being one selected from saturated and unsaturated compounds. 
     
     
       6. The promoter of claim 5, said cyclic compound being one selected from imidazolines, oxazolines, pyrroles and analogs thereof. 
     
     
       7. The promoter of claim 6, further comprising a C 1  to C 6  alkanol co-promoter. 
     
     
       8. The promoter of claim 7, wherein the total weight of promoter and co-promoter is less than about 8% of the overbased calcium sulfonate, and wherein the overbased calcium sulfonate has a TBN of at least about 300. 
     
     
       9. A process for preparing an overbased calcium sulfonate comprising: (a) providing a mxiture comprising a sulfonic acid or calcium salt thereof, a hydrocarbon solvent, calcium hydroxide or calcium oxide, a C 1  to C 6  alkanol, and as a promoter, a cyclic compound having the formula; ##STR12##  where X=O, S,═CH, --CH 2 , --NH or --N═; Y=O, N or S;   R=H or, C 1  to C 50  ; and   R'=H, CH 2  CH 2  OH, or CH 2  CH 2  NH 2  when Y is N, and zero when Y is O or S,     (b) contacting said mixture with an acidifying material at a temperature between 60° F. to 130° F. to form the product overbased calcium sulfonate, and wherein the cyclic compound is present in an amount of up to about 1.0% by weight of the product yield.   
     
     
       10. The process of claim 9, wherein the product overbased calcium sulfonate has a TBN of at least about 300. 
     
     
       11. The process of claim 10, wherein the total weight of the alkanol and cyclic promoter compound is about 8% of the product sulfonate. 
     
     
       12. The process of claim 11, said cyclic promoter compound being an alkyl imidazoline. 
     
     
       13. The process of claim 9, wherein the alkanol is present in an amount of less than about 4%. 
     
     
       14. The process of calim 13, wherein the cyclic compound is present in an amount of up to about 1.0%. 
     
     
       15. An overbased calcium sulfonate comprising; an overbased calcium sulfonate comprising a cyclic promoter having the formula: ##STR13## where X=O, S,═CH, --CH 2 , --NH or --N═ Y=O, N or S;   R=H or, C 1  C 50  ; and   R'=H, CH 2 , CH 2  OH, or CH 2  CH 2  NH 2  when Y is N, and zero when Y is O or S, wherein the cyclic promoter is present in an amount up to about 1.0% by weight of the calcium sulfonate.     
     
     
       16. The overbased calcium sulfonate of claim 15, said sulfonate having a TBN of at least about 300. 
     
     
       17. The overbased calcium sulfonate of claim 16, said promoter being one selected from an imidazoline, oxazoline and pyrrole and an analog thereof.